Handling your lipo's well is indeed lengthening the life span but i am not sure about the refrigerator thing. It might seem that it works but there is no scientific explaination for that. Basically if you let a lipo sit at 20% it should be fine.
It'll age anyway.
BTW, nice that you can keep using it for 3 years. I never had mine that long thought. Also depends what you do with it. It makes a difference if you use a lipo in a simple car or a complex 3d helicopter.